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1.
J Pharm Biomed Anal ; 172: 339-348, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31085396

RESUMEN

Gamma-oryzanol (GO) has gained special attention in the equine sports industry in recent years due to its touted properties, including the fact that it may cause anabolic effects on muscle growth and reduce fatigue. Many manufactures offer supplements containing GO as a naturally occurring anabolic substance; however, some producers do not declare its presence in product compositions. Taking into consideration the touted properties of GO, its ambiguous effectiveness and the open character of the Prohibited Substances List established by the Fédération Equestre Internationale, there is an urgent need to elaborate procedures for the estimation of horse exposure to GO during supplementation, as well as during routine analysis of supplements. This work describes the development and validation of the method for determination of the four main GO components, i.e., cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and ß-sitosteryl ferulate, in equestrian supplements based on LC-MS/MS after a simple ultrasound-assisted extraction (Eco-Scale score value of 76). The analytical performance achieved satisfactory results in terms of linearity (R2 > 0.9910), sensitivity (LODs ranged from 0.4 to 1.9 ng/mL), intra- and interday accuracy (from 90.4-115.8%), precision (CV < 9.6%) and recovery (from 87.6-108.6%) for all of the investigated compounds. The method was successfully applied to the analysis of thirty equestrian supplements.


Asunto(s)
Suplementos Dietéticos/análisis , Fenilpropionatos/química , Anabolizantes/química , Animales , Cromatografía Líquida de Alta Presión/métodos , Ácidos Cumáricos/química , Caballos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos , Congéneres de la Testosterona/química
2.
Tidsskr Nor Laegeforen ; 139(4)2019 02 26.
Artículo en Inglés, Noruego | MEDLINE | ID: mdl-30808106

RESUMEN

BACKGROUND: International studies have shown that 12-58 % of all dietary supplements intended for people who exercise and engage in sports contain substances prohibited by the World Anti-Doping Code (WADC). In some cases, the doping substances are not declared on the product label, and the consumer may therefore be unaware of what he/she ingests. Many of the substances may cause adverse health effects, and sale of such products is illegal in Norway. MATERIAL AND METHOD: To investigate the prevalence of doping substances in dietary supplements sold on the Norwegian market, a total of 93 high-risk products from online shops targeting Norwegian consumers were analysed for substances on the WADC Prohibited List and pharmaceutical drugs. All supplements were marketed as able to boost energy levels and/or having a muscle-building or fat-burning effect. The products were selected on the basis of tips received, online forums and/or international lists. RESULTS: Altogether 21 of 93 (23 %) products analysed contained prohibited substances, pharmaceutical drugs and/or illegal amounts of caffeine. Substances on the WADC Prohibited List were detected in 8 of the 93 (9 %) dietary supplements. All products containing doping substances were declared as containing one or more banned substances. INTERPRETATION: The results show that using apparently legal dietary supplements purchased in online shops targeting Norwegian consumers involves a risk of inadvertent doping and adverse health effects.


Asunto(s)
Suplementos Dietéticos/análisis , Sustancias para Mejorar el Rendimiento/química , Anabolizantes/química , Fármacos Antiobesidad/química , Cafeína/química , Doping en los Deportes , Humanos , Internet , Noruega , Preparaciones Farmacéuticas/química
3.
Steroids ; 138: 134-160, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30118779

RESUMEN

Several studies have highlighted that nutritional supplements may contain undeclared anabolic steroids that are banned by the International Olympic Committee/World Anti-Doping Agency. Any kind of abuse with these drugs is extremely dangerous because of their side effects. Thus, the control of food additives in order to protect the best consumer health and to limit fraudulent practices in the field of sports is essential. This paper describes a simple and effective qualitative gas chromatography-mass spectrometry (GC-MS) method to detect anabolic androgenic steroids (AAS): androsterone, nandrolene, dehydroepiandrosterone, 5ɑ-androstane-3ß, 17ß-diol, dihydrotestosterone, testosterone, methenolone acetate, methandienone, boldenone and fluoxymesterone, in food supplements. Methyltestosterone was used as internal standard. Target compounds were extracted with a mixture of N-pentane and di-ethylether (7.5:2.5, v/v). A good extraction recovery was obtained by our method for all the AAS (R > 88%). Crude extract was derivatized with N-methyl-N-trimethylsilyl-trifluoracetamide. Separation was performed on a GC connected to quadrupole MS detector using a 5% phenylmethylsiloxane fused silica capillary column (30 m × 0.25 mm i.d.; film thickness, 0.25 µm). Helium was used as carrier gas with a flow rate of 0.3 µl min-1 (measured at 6.1 psi 190 °C). The MS was operated in electron ionization mode (70 eV) and in selected ion monitoring (SIM). The mass spectra of the standard compounds were acquired in full SCAN mode (50-700 m/z) by infusion of a reference solution at 50 µg/ml. Three higher diagnostic ions were monitored for each compound of interest. All AAS get separated with good peak shapes and resolution factor. The total analysis time by our optimised method was only 20 min. The developed method was validated according to Laboratories International Standard regulations for specificity, precision in both liquid and solid matrixes, and memory effect. The Tolerance Interval was judged true. The limit of detection was about 10 ng/g for solid samples and 10 ng/ml for liquid samples. The developed method was then applied to the research of steroids in nine Tunisian commercially dietary supplements using for each compound of interest SIM mode for screening then SCAN mode for confirmation. One of the monitoring samples was positive to methandienone not declared on the label. Our analytical method can be beneficial for AAS screening in dietary supplements.


Asunto(s)
Suplementos Dietéticos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Congéneres de la Testosterona/aislamiento & purificación , Anabolizantes/química , Anabolizantes/aislamiento & purificación , Cromatografía de Gases , Doping en los Deportes , Humanos , Espectrometría de Masas , Congéneres de la Testosterona/química
4.
J Int Soc Sports Nutr ; 14: 30, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28852372

RESUMEN

The branched chain amino acids (BCAAs) are leucine, valine and isoleucine. A multi-million dollar industry of nutritional supplements has grown around the concept that dietary supplements of BCAAs alone produce an anabolic response in humans driven by a stimulation of muscle protein synthesis. In this brief review the theoretical and empirical bases for that claim are discussed. Theoretically, the maximal stimulation of muscle protein synthesis in the post-absorptive state in response to BCAAs alone is the difference between muscle protein breakdown and muscle protein synthesis (about 30% greater than synthesis), because the other EAAs required for synthesis of new protein can only be derived from muscle protein breakdown. Realistically, a maximal increase in muscle protein synthesis of 30% is an over-estimate because the obligatory oxidation of EAAs can never be completely suppressed. An extensive search of the literature has revealed no studies in human subjects in which the response of muscle protein synthesis to orally-ingested BCAAs alone was quantified, and only two studies in which the effect of intravenously infused BCAAs alone was assessed. Both of these intravenous infusion studies found that BCAAs decreased muscle protein synthesis as well as protein breakdown, meaning a decrease in muscle protein turnover. The catabolic state in which the rate of muscle protein breakdown exceeded the rate of muscle protein synthesis persisted during BCAA infusion. We conclude that the claim that consumption of dietary BCAAs stimulates muscle protein synthesis or produces an anabolic response in human subjects is unwarranted.


Asunto(s)
Aminoácidos de Cadena Ramificada/química , Anabolizantes/química , Proteínas Musculares/biosíntesis , Dieta , Suplementos Dietéticos , Humanos , Biosíntesis de Proteínas
5.
Arch Immunol Ther Exp (Warsz) ; 65(1): 21-36, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27326424

RESUMEN

Alpha-ketoglutarate (AKG), an endogenous intermediary metabolite in the Krebs cycle, is a molecule involved in multiple metabolic and cellular pathways. It functions as an energy donor, a precursor in the amino acid biosynthesis, a signalling molecule, as well as a regulator of epigenetic processes and cellular signalling via protein binding. AKG is an obligatory co-substrate for 2-oxoglutarate-dependent dioxygenases, which catalyse hydroxylation reactions on various types of substrates. It regulates the activity of prolyl-4 hydroxylase, which controls the biosynthesis of collagen, a component of bone tissue. AKG also affects the functioning of prolyl hydroxylases, which, in turn, influences the function of the hypoxia-inducible factor, an important transcription factor in cancer development and progression. Additionally, it affects the functioning of enzymes that influence epigenetic modifications of chromatin: ten-eleven translocation hydroxylases involved in DNA demethylation and the Jumonji C domain containing lysine demethylases, which are the major histone demethylases. Thus, it regulates gene expression. The metabolic and extrametabolic function of AKG in cells and the organism open many different fields for therapeutic interventions for treatment of diseases. This review presents the results of studies conducted with the use of AKG in states of protein deficiency and oxidative stress conditions. It also discusses current knowledge about AKG as an immunomodulatory agent and a bone anabolic factor. Additionally, the regulatory role of AKG and its structural analogues in carcinogenesis as well as the results of studies of AKG as an anticancer agent are discussed.


Asunto(s)
Ácidos Cetoglutáricos/uso terapéutico , Anabolizantes/química , Animales , Antineoplásicos/química , Antineoplásicos/inmunología , Antioxidantes/química , Ciclo del Ácido Cítrico , Metilación de ADN , Suplementos Dietéticos , Epigénesis Genética , Humanos , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/química , Mutación , Estrés Oxidativo , Transducción de Señal
6.
Artículo en Inglés | MEDLINE | ID: mdl-27092588

RESUMEN

In 2013 the Dutch authorities issued a warning against a dietary supplement that was linked to 11 reported adverse reactions, including heart problems and in one case even a cardiac arrest. In the UK a 20-year-old woman, said to have overdosed on this supplement, died. Since according to the label the product was a herbal mixture, initial LC-MS/MS analysis focused on the detection of plant toxins. Yohimbe alkaloids, which are not allowed to be present in herbal preparations according to Dutch legislation, were found at relatively high levels (400-900 mg kg(-1)). However, their presence did not explain the adverse health effects reported. Based on these effects the supplement was screened for the presence of a ß-agonist, using three different biosensor assays, i.e. the validated competitive radioligand ß2-adrenergic receptor binding assay, a validated ß-agonists ELISA and a newly developed multiplex microsphere (bead)-based ß-agonist assay with imaging detection (MAGPIX(®)). The high responses obtained in these three biosensors suggested strongly the presence of a ß-agonist. Inspection of the label indicated the presence of N-isopropyloctopamine. A pure standard of this compound was bought and shown to have a strong activity in the three biosensor assays. Analysis by LC-full-scan high-resolution MS confirmed the presence of this 'unknown known' ß3-agonist N-isopropyloctopamine, reported to lead to heart problems at high doses. A confirmatory quantitative analysis revealed that one dose of the preparation resulted in an intake of 40-60 mg, which is within the therapeutic range of this compound. The case shows the strength of combining bioassays with chemical analytical techniques for identification of illegal pharmacologically active substances in food supplements.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 3/envenenamiento , Antipirina/análogos & derivados , Depresores del Apetito/efectos adversos , Suplementos Dietéticos/efectos adversos , Contaminación de Alimentos , Cardiopatías/etiología , Preparaciones de Plantas/efectos adversos , Agonistas de Receptores Adrenérgicos beta 3/análisis , Alcaloides/análisis , Alcaloides/toxicidad , Anabolizantes/efectos adversos , Anabolizantes/química , Anabolizantes/envenenamiento , Anabolizantes/normas , Antipirina/análisis , Antipirina/envenenamiento , Depresores del Apetito/química , Depresores del Apetito/envenenamiento , Depresores del Apetito/normas , Técnicas Biosensibles , Suplementos Dietéticos/análisis , Suplementos Dietéticos/envenenamiento , Suplementos Dietéticos/normas , Inspección de Alimentos , Etiquetado de Alimentos , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/mortalidad , Enfermedades Transmitidas por los Alimentos/terapia , Cardiopatías/mortalidad , Cardiopatías/terapia , Hospitalización , Humanos , Internet , Países Bajos , Nootrópicos/efectos adversos , Nootrópicos/química , Nootrópicos/envenenamiento , Nootrópicos/normas , Pausinystalia/efectos adversos , Pausinystalia/química , Sustancias para Mejorar el Rendimiento/efectos adversos , Sustancias para Mejorar el Rendimiento/química , Sustancias para Mejorar el Rendimiento/envenenamiento , Sustancias para Mejorar el Rendimiento/normas , Preparaciones de Plantas/química , Preparaciones de Plantas/envenenamiento , Preparaciones de Plantas/normas
7.
Curr Neuropharmacol ; 13(1): 89-100, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26074745

RESUMEN

Anabolic androgenic steroids (AAS) are some of the most common performance enhancing drugs (PED) among society. Despite the broad spectrum of adverse effects and legal consequences, AAS are illicitly marketed and distributed in many countries. To circumvent existing laws, the chemical structure of AAS is modified and these designer steroids are sold as nutritional supplements mainly over the Internet. Several side effects are linked with AAS abuse. Only little is known about the pharmacological effects and metabolism of unapproved steroids due to the absence of clinical studies. The large number of designer steroid findings in dietary supplements and the detection of new compounds combined with legal loopholes for their distribution in many countries show that stricter regulations and better information policy are needed.


Asunto(s)
Drogas de Diseño/farmacología , Esteroides/farmacología , Congéneres de la Testosterona/farmacología , Anabolizantes/química , Anabolizantes/farmacología , Drogas de Diseño/efectos adversos , Drogas de Diseño/química , Suplementos Dietéticos/efectos adversos , Humanos , Esteroides/efectos adversos , Esteroides/química , Trastornos Relacionados con Sustancias/epidemiología , Congéneres de la Testosterona/efectos adversos , Congéneres de la Testosterona/química
8.
Cell Death Dis ; 4: e778, 2013 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-23969857

RESUMEN

Withania somnifera or Ashwagandha is a medicinal herb of Ayurveda. Though the extract and purified molecules, withanolides, from this plant have been shown to have different pharmacological activities, their effect on bone formation has not been studied. Here, we show that one of the withanolide, withaferin A (WFA) acts as a proteasomal inhibitor (PI) and binds to specific catalytic ß subunit of the 20S proteasome. It exerts positive effect on osteoblast by increasing osteoblast proliferation and differentiation. WFA increased expression of osteoblast-specific transcription factor and mineralizing genes, promoted osteoblast survival and suppressed inflammatory cytokines. In osteoclast, WFA treatment decreased osteoclast number directly by decreasing expression of tartarate-resistant acid phosphatase and receptor activator of nuclear factor kappa-B (RANK) and indirectly by decreasing osteoprotegrin/RANK ligand ratio. Our data show that in vitro treatment of WFA to calvarial osteoblast cells decreased expression of E3 ubiquitin ligase, Smad ubiquitin regulatory factor 2 (Smurf2), preventing degradation of Runt-related transcription factor 2 (RunX2) and relevant Smad proteins, which are phosphorylated by bone morphogenetic protein 2. Increased Smurf2 expression due to exogenous treatment of tumor necrosis factor α (TNFα) to primary osteoblast cells was decreased by WFA treatment. This was corroborated by using small interfering RNA against Smurf2. Further, WFA also blocked nuclear factor kappa-B (NF-kB) signaling as assessed by tumor necrosis factor stimulated nuclear translocation of p65-subunit of NF-kB. Overall data show that in vitro proteasome inhibition by WFA simultaneously promoted osteoblastogenesis by stabilizing RunX2 and suppressed osteoclast differentiation, by inhibiting osteoclastogenesis. Oral administration of WFA to osteopenic ovariectomized mice increased osteoprogenitor cells in the bone marrow and increased expression of osteogenic genes. WFA supplementation improved trabecular micro-architecture of the long bones, increased biomechanical strength parameters of the vertebra and femur, decreased bone turnover markers (osteocalcin and TNFα) and expression of skeletal osteoclastogenic genes. It also increased new bone formation and expression of osteogenic genes in the femur bone as compared with vehicle groups (Sham) and ovariectomy (OVx), Bortezomib (known PI), injectible parathyroid hormone and alendronate (FDA approved drugs). WFA promoted the process of cortical bone regeneration at drill-holes site in the femur mid-diaphysis region and cortical gap was bridged with woven bone within 11 days of both estrogen sufficient and deficient (ovariectomized, Ovx) mice. Together our data suggest that WFA stimulates bone formation by abrogating proteasomal machinery and provides knowledge base for its clinical evaluation as a bone anabolic agent.


Asunto(s)
Anabolizantes/farmacología , Huesos/patología , Osteoporosis/tratamiento farmacológico , Inhibidores de Proteasoma/química , Witanólidos/farmacología , Cicatrización de Heridas , Anabolizantes/química , Anabolizantes/farmacocinética , Anabolizantes/uso terapéutico , Animales , Biomarcadores/metabolismo , Fenómenos Biomecánicos/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/genética , Huesos/efectos de los fármacos , Huesos/fisiopatología , Calcificación Fisiológica/efectos de los fármacos , Calcificación Fisiológica/genética , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Femenino , Fémur/efectos de los fármacos , Fémur/patología , Fémur/fisiopatología , Ratones , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/patología , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteoclastos/patología , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Osteoporosis/genética , Osteoporosis/patología , Osteoporosis/fisiopatología , Ovariectomía , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacocinética , Inhibidores de Proteasoma/farmacología , Inhibidores de Proteasoma/uso terapéutico , Proteolisis/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Witanólidos/química , Witanólidos/farmacocinética , Witanólidos/uso terapéutico , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/genética
9.
Steroids ; 78(11): 1047-52, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23891647

RESUMEN

Musk is widely used as a traditional drug in Asia for the treatment of stroke, tumour, and cardiopathy with an oral dosage of 0.03-0.1 g per day. Because of the potential anabolic effect, musk preparations have been included in the list of medical products containing prohibited substances employed for doping. The application of musk pod formulation was regarded as the reason of some adverse analytical findings in the 2011 FIFA Women's World Cup. In order to investigate the influence of musk administration on the doping test, we executed a chemical analysis and excretion study. The gas chromatography/mass spectrometry (GC-MS) analysis demonstrated the diversity of steroid concentrations in musk samples. Furthermore, the δ(13)C-values of steroids from wild deer musk showed more depleted than those of domestic deer musk by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) analysis. Because the steroids from some musk had δ(13)C-values in the range of naturally produced steroids in human body, the possible abuse of this kind of musk is very hard to be detected by isotope ratio mass spectrometry (IRMS) in doping control. Musk grains from wild and domestic deer were administrated for the excretion study respectively. Spot urine samples were collected from two male volunteers before and after 100 mg musk grains administration. The profiles and carbon isotope ratios of urinary steroids were determined by GC-MS and GC/C/IRMS. The ingestion of either wild or domestic deer musk did not lead to the adverse analytical finding of doping control in the single dosage of 100mg.


Asunto(s)
Anabolizantes/farmacología , Doping en los Deportes , Ácidos Grasos Monoinsaturados/farmacología , Medicina Tradicional , Esteroides/orina , Adulto , Anabolizantes/administración & dosificación , Anabolizantes/química , Animales , Isótopos de Carbono/química , Ciervos , Doping en los Deportes/prevención & control , Ácidos Grasos Monoinsaturados/administración & dosificación , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Adulto Joven
10.
Drug Test Anal ; 3(5): 331-6, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21538997

RESUMEN

Identifying the use of non-approved drugs by cheating athletes has been a great challenge for doping control laboratories. This is due to the additional complexities associated with identifying relatively unknown and uncharacterized compounds and their metabolites as opposed to known and well-studied therapeutics. In 2010, the prohibited drug candidates and gene doping substances AICAR and GW1516, together with the selective androgen receptor modulator (SARM) MK-2866 were obtained by the Cologne Doping Control Laboratory from Internet suppliers and their structure, quantity, and formulation elucidated. All three compounds proved authentic as determined by liquid chromatography-high resolution/high accuracy (tandem) mass spectrometry and comparison to reference material. While AICAR was provided as a colourless powder in 100 mg aliquots, GW1516 was obtained as an orange/yellow suspension in water/glycerol (150 mg/ml), and MK-2866 (25 mg/ml) was shipped dissolved in polyethylene glycol (PEG) 300. In all cases, the quantified amounts were considerably lower than indicated on the label. The substances were delivered via courier, with packaging identifying them as containing 'amino acids' and 'green tea extract', arguably to circumvent customs control. Although all of the substances were declared 'for research only', their potential misuse in illicit performance-enhancement cannot be excluded; moreover sports drug testing authorities should be aware of the facile availability of black market copies of these drug candidates.


Asunto(s)
Anabolizantes/análisis , Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias/métodos , Amidas/análisis , Amidas/química , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/análisis , Aminoimidazol Carboxamida/química , Anabolizantes/química , Anilidas , Cromatografía Liquida , Humanos , Drogas Ilícitas/análisis , Internet , Espectrometría de Masas , Polietilenglicoles/química , Ribonucleótidos/análisis , Ribonucleótidos/química , Solventes/química , Tiazoles/análisis , Tiazoles/química
11.
Bioorg Med Chem ; 19(6): 1881-94, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21353570

RESUMEN

The calcium-sensing receptor antagonist (CaSR) has been recognized as a promising target of anabolic agents for treating osteoporosis. In the course of developing a new drug candidate for osteoporosis, we found tetrahydropyrazolopyrimidine derivative 1 to be an orally active CaSR antagonist that stimulated transient PTH secretion in rats. However, compound 1 showed poor physical and chemical stability. In order to work out this compound's chemical stability and further understand its in vivo efficacy, we focused on modifying the 2-position of the tetrahydropyrazolopyrimidine. As a result of chemical modification, we discovered (5R)-N-[1-ethyl-1-(4-ethylphenyl)propyl]-2,7,7-trimethyl-5-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-3-carboxamide monotosylate 10m (TAK-075), which showed improved solubility, chemical stability, and in vivo efficacy. Furthermore, we describe that evaluating the active metabolite is important during repeated treatment with short-acting CaSR antagonists.


Asunto(s)
Anabolizantes/química , Pirazoles/química , Pirimidinas/química , Receptores Sensibles al Calcio/antagonistas & inhibidores , Administración Oral , Anabolizantes/farmacocinética , Anabolizantes/uso terapéutico , Animales , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Humanos , Macaca fascicularis , Conformación Molecular , Osteoporosis/tratamiento farmacológico , Hormona Paratiroidea/metabolismo , Pirazoles/síntesis química , Pirazoles/uso terapéutico , Pirimidinas/síntesis química , Pirimidinas/farmacocinética , Pirimidinas/uso terapéutico , Ratas , Receptores Sensibles al Calcio/metabolismo
12.
Chem Res Toxicol ; 23(6): 1115-26, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20507089

RESUMEN

The synthesis and structure-activity relationship studies on 5-trifluoromethylpyrido[4,3-d]pyrimidin-4(3H)-ones as antagonists of the human calcium receptor (CaSR) have been recently disclosed [ Didiuk et al. ( 2009 ) Bioorg. Med. Chem. Lett. 19 , 4555 - 4559 ). On the basis of its pharmacology and disposition attributes, (R)-2-(2-hydroxyphenyl)-3-(1-phenylpropan-2-yl)-5-(trifluoromethyl)pyrido[4,3-d]pyrimidin-4(3H)-one (1) was considered for rapid advancement to first-in-human (FIH) trials to mitigate uncertainty surrounding the pharmacokinetic/pharmacodynamic (PK/PD) predictions for a short-acting bone anabolic agent. During the course of metabolic profiling, however, glutathione (GSH) conjugates of 1 were detected in human liver microsomes in an NADPH-dependent fashion. Characterization of the GSH conjugate structures allowed insight(s) into the bioactivation pathway, which involved CYP3A4-mediated phenol ring oxidation to the catechol, followed by further oxidation to the electrophilic ortho-quinone species. While the reactive metabolite (RM) liability raised concerns around the likelihood of a potential toxicological outcome, a more immediate program goal was establishing confidence in human PK predictions in the FIH study. Furthermore, the availability of a clinical biomarker (serum parathyroid hormone) meant that PD could be assessed side by side with PK, an ideal scenario for a relatively unprecedented pharmacologic target. Consequently, progressing 1 into the clinic was given a high priority, provided the compound demonstrated an adequate safety profile to support FIH studies. Despite forming identical RMs in rat liver microsomes, no clinical or histopathological signs prototypical of target organ toxicity were observed with 1 in in vivo safety assessments in rats. Compound 1 was also devoid of metabolism-based mutagenicity in in vitro (e.g., Salmonella Ames) and in vivo assessments (micronuclei induction in bone marrow) in rats. Likewise, metabolism-based studies (e.g., evaluation of detoxicating routes of clearance and exhaustive PK/PD studies in animals to prospectively predict the likelihood of a low human efficacious dose) were also conducted, which mitigated the risks of idiosyncratic toxicity to a large degree. In parallel, medicinal chemistry efforts were initiated to identify additional compounds with a complementary range of human PK predictions, which would maximize the likelihood of achieving the desired PD effect in the clinic. The back-up strategy also incorporated an overarching goal of reducing/eliminating reactive metabolite formation observed with 1. Herein, the collective findings from our discovery efforts in the CaSR program, which include the incorporation of appropriate derisking steps when dealing with RM issues are summarized.


Asunto(s)
Anabolizantes/química , Anabolizantes/metabolismo , Osteoporosis/tratamiento farmacológico , Piridinas/química , Piridinas/metabolismo , Pirimidinonas/química , Pirimidinonas/metabolismo , Receptores Sensibles al Calcio/antagonistas & inhibidores , Anabolizantes/efectos adversos , Animales , Cristalografía por Rayos X , Humanos , Piridinas/efectos adversos , Pirimidinonas/efectos adversos , Ratas
13.
Handb Exp Pharmacol ; (195): 155-85, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20020364

RESUMEN

Anabolic steroids have been studied for over 50 years and during that time numerous compounds with a variety of functional groups have been produced and many have been published. Of these only a small number have been introduced to the pharmaceutical market. WADA has continued the work begun by the IOC banning the use of these agents within sport as performance enhancing substances. Athletes, however, continue to use these anabolic steroids but tighter testing and the introduction of unannounced sample collection has made this form of cheating harder.In order to try to evade detection, athletes who continue to dope are having to resort to the use of a far more dangerous form of drug - the designer steroid. These steroids are manufactured to closely resemble existing known compounds, but with sufficient chemical diversity to ensure that their detection by the WADA accredited laboratories is more difficult. A worrying feature of the use of these compounds is that no data is available to evaluate either the efficacy or the safety of these substances. Many such drugs are now being made in clandestine ways (as demonstrated by the recent BALCO case) and then passed on to athletes who become the guinea pigs determining the potential of the substances as doping agents.Methods for the detection of these new compounds are being developed using emerging techniques such as gas chromatography or liquid chromatography attached to a variety of mass spectrometry instruments. This technology as well as vigilance by laboratories and enforcement agencies can all help in early detection of designer steroids being used for doping.


Asunto(s)
Anabolizantes/química , Anabolizantes/farmacología , Drogas de Diseño/química , Drogas de Diseño/farmacología , Doping en los Deportes/métodos , Esteroides/química , Esteroides/farmacología , Anabolizantes/síntesis química , Animales , Cromatografía Liquida , Drogas de Diseño/síntesis química , Suplementos Dietéticos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectrometría de Masas , Esteroides/síntesis química
14.
Steroids ; 74(8): 684-93, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19463691

RESUMEN

Anabolic steroids are widely used to increase skeletal muscle (SM) mass and improve physical performance. Some dietary supplements also include potent steroid precursors or active steroid analogs such as nandrolone. Our previous study reported the anabolic steroid effects on SM in a castrated guinea pig model with SM measured using a highly quantitative magnetic resonance imaging (MRI) protocol. The aim of the current study was to apply this animal model and in vivo MRI protocol to evaluate the growth effects of four widely used over-the-counter testosterone and nandrolone precursors: 4-androstene-3 17-dione (androstenedione), 4-androstene-3beta 17beta-diol (4-androsdiol), 19-nor-4-androstene-3beta-17beta-diol (bolandiol) and 19-nor-4-androstene-3 17-dione (19-norandrostenedione). The results showed that providing precursor to castrated male guinea pigs led to plasma steroid levels sufficient to maintain normal SM growth. The anabolic growth effects of these specific precursors on individual and total muscle volumes, sexual organs, and total adipose tissue over a 10-week treatment period, in comparison with those in the respective positive control testosterone and nandrolone groups, were documented quantitatively by MRI.


Asunto(s)
Anabolizantes/química , Anabolizantes/farmacología , Esteroides/química , Esteroides/farmacología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Anabolizantes/administración & dosificación , Animales , Peso Corporal/efectos de los fármacos , Cápsulas , Castración , Suplementos Dietéticos , Dimetilpolisiloxanos/química , Genitales Masculinos/efectos de los fármacos , Genitales Masculinos/crecimiento & desarrollo , Cobayas , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Animales , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/crecimiento & desarrollo , Nandrolona/sangre , Esteroides/administración & dosificación , Testosterona/sangre
15.
Artículo en Inglés | MEDLINE | ID: mdl-18473210

RESUMEN

A simple and effective analytical method for the determination of anabolic steroids and related compounds in nutritional supplements is reported. Target compounds are extracted with ethyl acetate, crude extract is purified using dispersive solid-phase extraction (SPE) with primary secondary amine (PSA) as sorbent, and finally they are identified and quantified as underivatized compounds using two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GCxGC-TOF MS). This method was validated for 25 steroids in two types of commercially available solid nutritional supplements: protein concentrate and creatine monohydrate. Repeatability expressed as the relative standard deviation of analyte concentration ranged from 4.1 to 20.5%. Recoveries between 70.0 and 122.6% were obtained for the target compounds except for oxymetholone in protein concentrate where the recovery was low as a result of strong interactions with PSA. Excellent linearity was obtained for six-point calibration with regression coefficients of 0.997-1.000 for all compounds. The limits of quantification ranged from 0.007 to 0.114 mg kg(-1). For a monitoring programme of 48 samples of nutritional supplements, three were positive. Nandrolone, testosterone, dehydroepiandrosterone (DHEA), 5alpha-androstan-3,17-dione, 19-norandrostendione and progesterone were found in positive samples at concentrations between 0.022 and 0.398 mg kg(-1).


Asunto(s)
Anabolizantes/análisis , Suplementos Dietéticos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Anabolizantes/química , República Checa , Doping en los Deportes/prevención & control , Humanos , Estándares de Referencia
16.
17.
Anal Chim Acta ; 586(1-2): 35-42, 2007 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-17386694

RESUMEN

Nineteen different dietary supplements, ordered through the internet and intercepted by the Belgian pharmaceutical inspection at the post office, were analyzed by means of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the presence of anabolic steroids. After a methanolic extraction the samples were screened for the presence of 49 compounds. This resulted in almost 60% of the samples being suspected of containing one of these 49 anabolic compounds and being subjected to a confirmatory product ion scan. In all of these suspected samples we were able to confirm at least one anabolic steroid with concentrations between 0.01 and 2.5 mg unit(-1) (unit: one capsule or tablet or for liquids: the prescribed dose). The anabolic steroids that was mostly encountered was testosterone (50%) followed by beta-boldenone (25%). These results once more confirm the dubious reputation of over-the-counter dietary supplements.


Asunto(s)
Anabolizantes/análisis , Cromatografía Liquida/métodos , Suplementos Dietéticos/análisis , Espectrometría de Masas/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Esteroides/análisis , Detección de Abuso de Sustancias/métodos , Anabolizantes/química , Química Farmacéutica/métodos , Doping en los Deportes , Humanos , Metanol/farmacología , Modelos Químicos , Reproducibilidad de los Resultados , Esteroides/química , Comprimidos
18.
J Chromatogr Sci ; 35(1): 38-42, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8989871

RESUMEN

This paper describes a general screening method for the determination of anabolic steroids in oil-based injectables, water suspensions, dietary supplements, and herbal drugs marketed in the form of capsules or tablets. The compounds are extracted into methanol, separated on a reversed-phase column with an acetonitrile-water gradient, and detected by using an ultraviolet visible (UV-vis) photodiode array detector and a particle beam mass spectrometric detector coupled in series. Identification is based on retention time, UV-vis spectra, and mass spectra. Mass spectral confirmation is accomplished by matching with a standard when available and by comparison with an electron impact mass spectra library that is either commercially available or generated in our laboratory. The tandem arrangement of the detectors provides qualitative and quantitative information from a single experiment by fully utilizing the inherent advantages associated with each detector. This method is applicable to all the anabolic steroids encountered in this laboratory so far.


Asunto(s)
Anabolizantes/análisis , Cromatografía Líquida de Alta Presión/métodos , Anabolizantes/química , Espectrometría de Masas , Espectrofotometría , Espectrofotometría Ultravioleta , Testosterona/análisis , Testosterona/química , Drogas Veterinarias/análisis , Drogas Veterinarias/química
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